Tuesday, January 22, 2013

Biting Wind, Cold Day Forthcoming

Winter...in all its brrrrisk glory is upon us. Winds have increased in the overnight hours and those snow showers and squalls have departed, leaving in their wake a cold, blustery day across the Delaware Valley's "frozen tundra". Our highs for the day have likely occurred at Midnight, as temperatures will stay cold through the course of the day ahead.

Philadelphia picked up 1.4" of snow last night as a band of snow developed ahead of a trough that pushed through last night. Those snow showers intensified quickly thanks to atmospheric instability and pushed through the city and New Jersey, bringing an inch or two to many locations from the city on northeast. The instability was enough to trigger some thunder snow showers along the Shore as the bands reached the coastline. Thanks to last night's snow, some roads will be slick in the region this morning as you head out the door...and it's cold and brisk to boot.

Below is the NAM's projection for 2 PM this afternoon -- teens northwest of I-95, 20-22 southeast. With a mix of clouds and sun around, it will be enough to coax an extra degree or two above raw model data (which sometimes can run colder/warmer than reality)...however the winds will be solidly in the 14-22 mph range from the west and northwest, yielding wind chills several degrees colder than reality. More clouds are possible north of the city than south...and a few snow showers or flurries are possible in the Poconos and in Central PA.

All that aside, expect a rather cold and windy day. Temperatures hanging out in the 19-24 range throughout the Delaware Valley during the course of the day, wind chills generally between 4 and 14. Tonight features lows in the mid teens in the city, around 10 in the outer burbs near Quakertown, and in the single digits in the Lehigh Valley and Poconos.